The Body Continued

The optimising of the aerodynamic conditions underneath the car was indeed necessary. The Capri, compared to the Escort, was not only aerodynamically better because of it's body design, it's engine, by using the exhaust-gas turbocharger manufactured by the company of Kuhnle, Kopp and Kausch (KKK) produced 100bhp more power. For all that, it's displacement of only 1427cc. Since motorsport regulations provided for a handicap factor of 1.4 for the use of a turbocharger, the cylinder volume on the registration papers came to 1997.8cc.

The Turbocharger

The turbocharged engine not only produced more power than an induction engine, but unfortunately, also higher temperatures. For example, the exhaust side of the cylinder head would heat up to around 800 degrees centigrade, making it necessary to use special materials. The exhaust manifold, which had a large diameter, was made of a special steel, a kind of chrome-nickel alloy.The turbocharged engine in the Zakspeed Capri operated with a boost pressure of 1.0 - 1.1 bar. This pressure was virtually at hand under all driving conditions, hence at any engine speed. A so-called "blow-off" valve operating according to the Garret principle, ensured that the boost pressure did not rise indefinitely at increasing engine speeds with powerfully blowing exhaust gases. This valve regulated the flow of exhaust gases, depending on the boost pressure. It allowed the exhaust gases to flow into the turbine only at a rate necessary to build up the boost pressure to the level it had been set at. The excess gases were diverted through another duct into the normal exhaust system.

Because of its forced breathing the turbocharged engine operated with a relatively low compression ratio. The Capris engine for example had a compression ratio of 7:1 and so, at top dead centre, the pistons did not have to extend as far into the combustion chamber as was the case with a high compression induction engine. This was the reason why the piston heads on a turbocharged engine were practically smooth, except for two semi-circular indentations for the intake valves. On the other hand the pistons in an induction engine needed deeply cut bores in order to avoid contact with the valves. The pistons were kept at the right temperature by splash lubrication cooling, i.e. they were constantly sprayed from the inside with a fine jet stream of oil. The Turbo Capris engine had sixteen valves, just like the induction engine used in the Escort of the period. Eight intake valves and eight exhaust valves kept up the supply line to the four in-line cylinders. The valves were controlled by two overhead camshafts driven by a cog belt.

There was no doubt in 1978 that the Turbo Capri, in terms of it's engine and it's chassis, was a completely new car. The only thing (apart from the wheels and parts of the suspension) that it had in common with its successful predecessor; was the distinctive black yellow and red design of the Zakspeed sponsor "Mampe". For the tradition rich producers of Liquors in Berlin (aswell as for Erich Zakowski) the Turbo Capri signalled the beginning of a new era; for the first time in their equally successful racing histories, they both switched over to the Capri.